Release [[Release_Notes_-_0.19|0.19]] of MythTV introduced the ability to control mythfrontend via a socket interface. Commands are sent and replies are received in text mode, there is no fancy xml interface or anything - it is meant to be able to be used via something as simple as telnet. This feature has to be enabled in the general settings of the [[frontend]] setup. The default port is 6546, so after restarting mythfrontend, you can test by telnetting to localhost on port 6546

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Release [[Release_Notes_-_0.19|0.19]] of MythTV introduced the ability to control mythfrontend via a socket interface. Commands are sent and replies are received in text mode, there is no fancy xml interface or anything - it is meant to be able to be used via something as simple as netcat. This feature has to be enabled in the general settings of the [[Mythfrontend|frontend]] setup. The default port is 6546, so after restarting mythfrontend, you can test by netcatting to localhost on port 6546

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<pre>telnet localhost 6546</pre>

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<pre>netcat localhost 6546</pre>

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There can be only one socket connection to mythfrontend at a time, if a new connection is opened, the old one will be automatically closed.

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See also [http://www.mythtv.org/docs/mythtv-HOWTO-11.html#ss11.6 MythTV docs on Telnet socket ]

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See also [http://www.mythtv.org/docs/mythtv-HOWTO-11.html#ss11.5 MythTV docs on control socket ]

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A utility to allow your Linux (or Windows) PC to emulate your local frontend keyboard using this interface can be found [http://www.phaze.org/mythtv/cmdline-mythremote.tgz here] [Hat tip: Greg Estabrooks] [Anyone know who wrote this? --[[User:Baylink|Baylink]] 16:08, 8 November 2007 (UTC)]

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{{Warning box|The frontend control socket does '''NOT''' implement the telnet protocol. It is a raw text-based TCP socket. The Telnet protocol expects certain behaviors and enforces 7-bit ASCII text, which the control socket does not follow and will cause complications if used. '''netcat''' exists as a nearly drop-in replacement for telnet, and will work fine for this purpose.}}

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= Supported Commands =

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== Supported Commands ==

For a list of supported commands, type "help". For help on a specific command, type "help COMMAND" (where COMMAND is the name of the command like "help jump").

For a list of supported commands, type "help". For help on a specific command, type "help COMMAND" (where COMMAND is the name of the command like "help jump").

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== jump ==

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=== jump ===

<pre>

<pre>

Usage: jump JUMPPOINT

Usage: jump JUMPPOINT

Line 55:

Line 54:

viewscheduled - Manage Recordings / Fix Conflicts

viewscheduled - Manage Recordings / Fix Conflicts

</pre>

</pre>

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== key ==

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=== key ===

<pre>

<pre>

key LETTER - Send the letter key specified

key LETTER - Send the letter key specified

Line 71:

Line 70:

== play ==

== play ==

<pre>

<pre>

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play channel up - Change channel Up

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play volume NUMBER% - Change volume to given percentage value

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play channel down - Change channel Down

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play channel up - Change channel Up

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play channel NUMBER - Change to a specific channel number

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play channel down - Change channel Down

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play chanid NUMBER - Change to a specific channel id (chanid)

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play channel NUMBER - Change to a specific channel number

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play file FILENAME - Play specified file

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play chanid NUMBER - Change to a specific channel id (chanid)

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play program CHANID yyyy-mm-ddThh:mm:ss

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play file FILENAME - Play FILENAME (FILENAME may be a file or a myth:// URL)

Some limitations exist in the front-end control protocol; especially with implementations that exist for plugins to MythTV. For instance it is not possible to list artists, albums or tracks in MythMusic, neither is it possible to add tracks to the current queue or change playback to something else without emulating key-presses, which requires knowledge of the exact position of the cursor by the application.

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MythMusic Rescan Workaround: It is not possible to have MythMusic re-scan for music; although it is possible to emulate this behaviour. Using MythWeb, go to settings -> MythTV -> Key bindings and select the host (or hosts) from the drop-down you would like to be able to initiate a rescan programatically. Look up the row called "Scan Music". add a Key you would like to use (make sure it isnt a key you require elsewhere in the application as this is a global key-binding. Save the changes, you may need to restart the front-end in question. send the relevant key-press via the network control port to initiate music-rescan. i.e. nc localhost 6546 then if you used F6; # key f6

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The above can also be done from a script, like so:

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<pre>

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nc localhost 6546 -i 1 <<EOS

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key f6

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quit

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EOS

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</pre>

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== IP Address availability ==

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As of 0.25, this feature now follows the IP settings for the current machine's profile, if configured in `mythtv-setup`. These are the BackendServerIP and BackendServerIP6 settings on the first page of the General section. If these settings are left blank, as would be the case on a dedicated frontend if the user had never run `mythtv-setup`, or if the defaults in those fields were intentionally blanked, this feature will automatically be available on all IPv6 address, and all private network IPv4 addresses. Per [http://tools.ietf.org/html/rfc1918 RFC1918], those addresses are:

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* 10.0.0.0 - 10.255.255.255

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* 172.16.0.0 - 172.31.255.255

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* 192.168.0.0 - 192.168.255.255

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Most users will find themselves within that last group of IP addresses.

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If one wishes to restrict the addresses that the control socket is available through, defining those fields in `mythtv-setup` will cause the control socket to only be available on those two addresses. Similarly, those can be used to select an IPv4 address outside those private network ranges. If one wants to unrestrict where the frontend listens, but is running on a combination frontend/backend, where `mythbackend` required those options be set for proper operation, the frontend can be forced to run on an independent machine profile. That value defaults to the current machine hostname. In 0.25, that value can be overridden using the LocalHostName parameter in mysql.txt as follows:

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{{code box|~/.mythtv/mysql.txt|

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<pre>

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...

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LocalHostName=myindependentfrontendprofilestring

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...

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</pre>

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}}

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In 0.26 and later, mysql.txt has been removed in favor of config.xml, which can be configured as follows:

Revision as of 17:11, 17 December 2012

Release 0.19 of MythTV introduced the ability to control mythfrontend via a socket interface. Commands are sent and replies are received in text mode, there is no fancy xml interface or anything - it is meant to be able to be used via something as simple as netcat. This feature has to be enabled in the general settings of the frontend setup. The default port is 6546, so after restarting mythfrontend, you can test by netcatting to localhost on port 6546

Warning: The frontend control socket does NOT implement the telnet protocol. It is a raw text-based TCP socket. The Telnet protocol expects certain behaviors and enforces 7-bit ASCII text, which the control socket does not follow and will cause complications if used. netcat exists as a nearly drop-in replacement for telnet, and will work fine for this purpose.

play

play volume NUMBER% - Change volume to given percentage value
play channel up - Change channel Up
play channel down - Change channel Down
play channel NUMBER - Change to a specific channel number
play chanid NUMBER - Change to a specific channel id (chanid)
play file FILENAME - Play FILENAME (FILENAME may be a file or a myth:// URL)
play program CHANID yyyy-MM-ddThh:mm:ss
- Play program with chanid & starttime
play program CHANID yyyy-MM-ddThh:mm:ss resume
- Resume program with chanid & starttime
play save preview
- Save preview image from current position
play save preview FILENAME
- Save preview image to FILENAME
play save preview FILENAME WxH
- Save preview image of size WxH
play seek beginning - Seek to the beginning of the recording
play seek forward - Skip forward in the video
play seek backward - Skip backwards in the video
play seek HH:MM:SS - Seek to a specific position
play speed pause - Pause playback
play speed normal - Playback at normal speed
play speed 1x - Playback at normal speed
play speed SPEEDx - Playback where SPEED must be a decimal
play speed 1/8x - Playback at 1/8x speed
play speed 1/4x - Playback at 1/4x speed
play speed 1/3x - Playback at 1/3x speed
play speed 1/2x - Playback at 1/2x speed
play stop - Stop playback
play music play - Resume playback (MythMusic)
play music pause - Pause playback (MythMusic)
play music stop - Stop Playback (MythMusic)
play music setvolume N - Set volume to number (MythMusic)
play music getvolume - Get current volume (MythMusic)
play music getmeta - Get metadata for current track (MythMusic)
play music file NAME - Play specified file (MythMusic)
play music track N - Switch to specified track (MythMusic)
play music url URL - Play specified URL (MythMusic)

exit

Terminates the session.

Limitations & Workarounds

Some limitations exist in the front-end control protocol; especially with implementations that exist for plugins to MythTV. For instance it is not possible to list artists, albums or tracks in MythMusic, neither is it possible to add tracks to the current queue or change playback to something else without emulating key-presses, which requires knowledge of the exact position of the cursor by the application.

MythMusic Rescan Workaround: It is not possible to have MythMusic re-scan for music; although it is possible to emulate this behaviour. Using MythWeb, go to settings -> MythTV -> Key bindings and select the host (or hosts) from the drop-down you would like to be able to initiate a rescan programatically. Look up the row called "Scan Music". add a Key you would like to use (make sure it isnt a key you require elsewhere in the application as this is a global key-binding. Save the changes, you may need to restart the front-end in question. send the relevant key-press via the network control port to initiate music-rescan. i.e. nc localhost 6546 then if you used F6; # key f6

The above can also be done from a script, like so:

nc localhost 6546 -i 1 <<EOS
key f6
quit
EOS

IP Address availability

As of 0.25, this feature now follows the IP settings for the current machine's profile, if configured in `mythtv-setup`. These are the BackendServerIP and BackendServerIP6 settings on the first page of the General section. If these settings are left blank, as would be the case on a dedicated frontend if the user had never run `mythtv-setup`, or if the defaults in those fields were intentionally blanked, this feature will automatically be available on all IPv6 address, and all private network IPv4 addresses. Per RFC1918, those addresses are:

10.0.0.0 - 10.255.255.255

172.16.0.0 - 172.31.255.255

192.168.0.0 - 192.168.255.255

Most users will find themselves within that last group of IP addresses.

If one wishes to restrict the addresses that the control socket is available through, defining those fields in `mythtv-setup` will cause the control socket to only be available on those two addresses. Similarly, those can be used to select an IPv4 address outside those private network ranges. If one wants to unrestrict where the frontend listens, but is running on a combination frontend/backend, where `mythbackend` required those options be set for proper operation, the frontend can be forced to run on an independent machine profile. That value defaults to the current machine hostname. In 0.25, that value can be overridden using the LocalHostName parameter in mysql.txt as follows:

~/.mythtv/mysql.txt

...
LocalHostName=myindependentfrontendprofilestring
...

In 0.26 and later, mysql.txt has been removed in favor of config.xml, which can be configured as follows:

Development

Modified:
trunk/mythtv/programs/mythfrontend/networkcontrol.cpp
Log:
Network Control socket interface changes.
Add some new valid keys. The list:
home, end, return, tab, backtab, insert, delete, plus, comma, minus,
period, numbersign (aka poundsign), dollar, percent, ampersand, parenleft,
parenright, asterisk, question, bar, pipe, and F13 through F24. This also
adds the ability to use the actual symbol for mose of these such as "key +"
instead of having to type "key plus".
Add the ability to send key combinations such as CTRL+B, ALT+F, etc.. The
four supported modifiers are CTRL, ALT, SHIFT, and META and they can be
used individually such as CTRL+B or together such as CTRL+ALT+B.
Fix some minor bugs related to case conversion, previously the code would
lower() the whole input command and then uppercase the few places that
needed it such as when passing a Qt::ISODateTime, now we just lower() when
comparing things that need case-insensitive comparisons.
For debugging purposes, add the ability to sleep in the middle of a key
combination. You can now use the keyword 'sleep' to sleep one second in
the middle of a key command. Here's a not-so-useful example:
"key down down sleep down enter"